Back in the day when I was working for Microsoft, I came across this issue more often then not. Users would call and complain that email is not flowing and everything is stuck in the queues also in the event viewer you can see the following events...

> Mount another store and move all the user's to that store and then delete the one with the disconnected SMTP mailbox

> Recreate the Smtp mailbox for that store, so here is how you can re-create the SMTP mailbox...

Follow carefully coz it does get confusing!

1. By using the LDP utility, locate the following container: CN=Storage Group,CN=InformationStore,CN=ServerName,CN=SERVERS,CN=Name of Administrative Group,CN=Administrative Groups,CN=Organization Name,CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=Domain Name

2. Find the information store that has the objectGUID property that is referenced in event 326. To do so, follow these steps: a. Open the Properties dialog box for each information store in the storage group.

b. Check the objectGUID property.

Note If you are using the ADSI Edit snap-in instead of the LDP utility, the GUID is shown in another format than the one that is contained in event 326. In this case, you have to convert the GUID. For more information, click the following article number to view the article in the Microsoft Knowledge Base: 322308 (http://support.microsoft.com/kb/322308/) Event ID 9554 appears ater you modify mailbox permissions

3. If the store is a public store, go to step 6. Because a public store does not have a system mailbox, you cannot verify that the SMTP mailbox is disconnected.

4. In Exchange System Manager, expand the mailboxes container, and then run the cleanup agent.

5. Verify that the SMTP (ServerName-{GUID of Mailbox Store}) object is present and that it is connected.

6. If the SMTP (ServerName-{GUID of Mailbox Store}) object is not present or if it is disconnected, follow these steps:

a. Start ADSI Edit, and then locate the following:CN=Connections,CN=Organization Name,CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=Domain Name

b. If an object that is named SMTP (ServerName-{GUID of Mailbox Store}) exists, delete it.

c. Right-click the connections container, and then create a new object that has the following attributes: Class: mailGateway cn: SMTP (ServerName-{GUID of Mailbox Store})

f. Verify that you now have an additional SMTP mailbox that appears to be connected.

g. To clear the disconnected SMTP mailbox, right-click the mailbox, and then click Purge.

7. Verify that mail flow works again. To resolve this problem if incorrect attributes are set for the SMTP mailbox, follow these steps: 1. Start ADSI Edit, and then locate the following object: CN=Connections,CN=Organization Name,CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=Domain Name 2. Make sure that the following attributes are correct: • homeMTA • homeMDB • legacyExchangeDN Note You must check the attribute values on the same global catalog server that is being referenced by the Exchange Server computer on which the message is stuck.